This invention relates generally to pump bearings and more particularly to pump thrust bearings which may be lubricated by the pumped product.
In general, a rigid thrust bearing cannot handle the applied loads in many heavy duty applications of pumps. This is, in part, due to the inability of a thrust bearing disc to form the desirable lubricant wedge at the face of the bearing, since the edges of the disc are parallel to the direction of rotation. The result is often high frictional power losses and excessive bearing and component wear in the pumps.
These difficulties may become more severe in the case of product lubrication, i.e., lubrication of the pump moving parts by the pumped product. Such products may have non-ideal viscosity and lubricity, so that they may have little tendency to form lubricant wedges; or if they form such wedges, they may provide inadequate lubricity to protect the bearing surfaces. Thus, standard thrust bearings in pumps, whether lubricated by the pumped product or by separate lubricating oil or grease, are subject to wear and degradation inherent to their design and application.
One approach to solving these problems provides a segmented thrust bearing with tiltable segments which each can form a lubricant wedge and also can distribute loads more uniformly than is the case with standard unitary bearings. These bearings, however, are composed of many parts and may be damaged by particles in contaminated lubricant which can pack into faying surfaces of the segments and their supports and interfere with their ability to change tilt in response to changing loads. Such immobilization may prevent formation of the lubricant wedge and lead to damage which shortens the life of the pump.
The foregoing illustrates limitations known to exist in currently offered thrust bearings in pumps. Thus, it would be advantageous to provide an alternative directed to overcoming one or more of the limitations set forth above. Accordingly, a suitable alternative is provided including features more fully disclosed hereinafter.